ColumnsEditorTab: Use nodeRef for Draggable

According to react-grid-layout/react-draggable#749 (comment) and https://github.com/react-grid-layout/react-draggable?tab=readme-ov-file#draggable-props this is a workaround to avoid the following warning:

```
Warning: findDOMNode is deprecated and will be removed in the next major release. Instead, add a ref directly to the element you want to reference. Learn more about using refs safely here: https://reactjs.org/link/strict-mode-find-node
```

src/Widgets/ColumnContainerWidget/ColumnsEditorTab.tsx

@@ -503,6 +503,7 @@ class GridLayoutEditor extends Component<
       if (nextColSize) {
         const leftBound = -(colSize - 1)
         const rightBound = nextColSize - 1
+        const nodeRef = createRef<HTMLDivElement>()
 
         innerContent.unshift(
           <Draggable
@@ -521,8 +522,12 @@ class GridLayoutEditor extends Component<
                 deltaColSize: Math.round(x / this.state.draggableGrid),
               })
             }
+            nodeRef={nodeRef}
           >
-            <div className={this.props.readOnly ? '' : 'grid-handle'} />
+            <div
+              ref={nodeRef}
+              className={this.props.readOnly ? '' : 'grid-handle'}
+            />
           </Draggable>,
         )
       } else if (colIndex < 5 && !this.props.readOnly) {